1
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Ziogas DC, Martinos A, Petsiou DP, Anastasopoulou A, Gogas H. Beyond Immunotherapy: Seizing the Momentum of Oncolytic Viruses in the Ideal Platform of Skin Cancers. Cancers (Basel) 2022; 14:2873. [PMID: 35740539 PMCID: PMC9221332 DOI: 10.3390/cancers14122873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/30/2022] [Accepted: 06/03/2022] [Indexed: 11/24/2022] Open
Abstract
Despite the durable remissions induced by ICIs and targeted therapies in advanced melanoma and non-melanoma skin cancers, both subtypes usually relapse. Many systematic therapies have been tested to increase efficacy and delay relapse in ICIs, but their success has been limited. Due the feasibility of this approach, skin cancers have become the ideal platform for intralesional infusions of many novel agents, including oncolytic viruses (OVs). Talimogene laherparepvec (T-VEC) was the first FDA-approved OV for the treatment of unresectable melanoma and this virus opened up further potential for the use of this class of agents, especially in combination with ICIs, in order to achieve deeper and longer immune-mediated responses. However, the recently announced phase III MASTERKEY-265 trial was not able to confirm that the addition of T-VEC to pembrolizumab treatment improves progression-free or overall survival over the use of pembrolizumab alone. Despite these results, numerous studies are currently active, evaluating T-VEC and several other OVs as monotherapies or in regimens with ICIs in different subtypes of skin cancer. This overview provides a comprehensive update on the evolution status of all available OVs in melanoma and non-melanoma skin cancers and summarizes the more interesting preclinical findings, the latest clinical evidence, and the future insights in relation to the expected selective incorporation of some of these OVs into oncological practice.
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Affiliation(s)
| | | | | | | | - Helen Gogas
- First Department of Medicine, School of Medicine, National and Kapodistrian University of Athens, 115 27 Athens, Greece; (D.C.Z.); (A.M.); (D.-P.P.); (A.A.)
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2
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Burgess HM, Vink EI, Mohr I. Minding the message: tactics controlling RNA decay, modification, and translation in virus-infected cells. Genes Dev 2022; 36:108-132. [PMID: 35193946 PMCID: PMC8887129 DOI: 10.1101/gad.349276.121] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
With their categorical requirement for host ribosomes to translate mRNA, viruses provide a wealth of genetically tractable models to investigate how gene expression is remodeled post-transcriptionally by infection-triggered biological stress. By co-opting and subverting cellular pathways that control mRNA decay, modification, and translation, the global landscape of post-transcriptional processes is swiftly reshaped by virus-encoded factors. Concurrent host cell-intrinsic countermeasures likewise conscript post-transcriptional strategies to mobilize critical innate immune defenses. Here we review strategies and mechanisms that control mRNA decay, modification, and translation in animal virus-infected cells. Besides settling infection outcomes, post-transcriptional gene regulation in virus-infected cells epitomizes fundamental physiological stress responses in health and disease.
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Affiliation(s)
- Hannah M Burgess
- Department of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - Elizabeth I Vink
- Department of Microbiology, New York University School of Medicine, New York, New York 10016, USA
| | - Ian Mohr
- Department of Microbiology, New York University School of Medicine, New York, New York 10016, USA
- Laura and Isaac Perlmutter Cancer Institute, New York University School of Medicine, New York, New York 10016, USA
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3
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Abd-Aziz N, Poh CL. Development of oncolytic viruses for cancer therapy. Transl Res 2021; 237:98-123. [PMID: 33905949 DOI: 10.1016/j.trsl.2021.04.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 04/15/2021] [Accepted: 04/19/2021] [Indexed: 02/07/2023]
Abstract
Oncolytic virotherapy is a therapeutic approach that uses replication-competent viruses to kill cancers. The ability of oncolytic viruses to selectively replicate in cancer cells leads to direct cell lysis and induction of anticancer immune response. Like other anticancer therapies, oncolytic virotherapy has several limitations such as viral delivery to the target, penetration into the tumor mass, and antiviral immune responses. This review provides an insight into the different characteristics of oncolytic viruses (natural and genetically modified) that contribute to effective applications of oncolytic virotherapy in preclinical and clinical trials, and strategies to overcome the limitations. The potential of oncolytic virotherapy combining with other conventional treatments or cancer immunotherapies involving immune checkpoint inhibitors and CAR-T therapy could form part of future multimodality treatment strategies.
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Affiliation(s)
- Noraini Abd-Aziz
- Centre for Virus and Vaccine Research (CVVR), School of Medical and Life Sciences, Sunway University, Subang Jaya, Selangor, Malaysia
| | - Chit Laa Poh
- Centre for Virus and Vaccine Research (CVVR), School of Medical and Life Sciences, Sunway University, Subang Jaya, Selangor, Malaysia.
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4
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Ang X, Xu Z, Zhou Q, Zhang Z, Ma L, Zhang X, Zhou F, Chen W. PARGP1, a specific enhancer RNA associated with biochemical recurrence of prostate cancer. ALL LIFE 2021. [DOI: 10.1080/26895293.2021.1969292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Xiaojie Ang
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - ZeKun Xu
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Qi Zhou
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Zhiyu Zhang
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Lu Ma
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Xi Zhang
- Department of Urology, Kunshan Hospital of Traditional Chinese Medicine, Kunshan, People’s Republic of China
| | - Feng Zhou
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Weiguo Chen
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
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5
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Turkington CJR, Varadan AC, Grenier SF, Grasis JA. The Viral Janus: Viruses as Aetiological Agents and Treatment Options in Colorectal Cancer. Front Cell Infect Microbiol 2021; 10:601573. [PMID: 33489934 PMCID: PMC7817644 DOI: 10.3389/fcimb.2020.601573] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 11/23/2020] [Indexed: 12/24/2022] Open
Abstract
In recent years, our understanding of the importance of microorganisms on and within our bodies has been revolutionized by the ability to characterize entire microbial communities. No more so is this true than in cases of disease. Community studies have revealed strong associations between microbial populations and disease states where such concomitance was previously absent from aetiology: including in cancers. The study of viruses, in particular, has benefited from the development of new community profiling techniques and we are now realising that their prominence within our physiology is nearly as broad as the diversity of the organisms themselves. Here, we examine the relationship between viruses and colorectal cancer (CRC), the leading cause of gastrointestinal cancer-related death worldwide. In CRC, viruses have been suggested to be involved in oncogenesis both directly, through infection of our cells, and indirectly, through modulating the composition of bacterial communities. Interestingly though, these characteristics have also led to their examination from another perspective—as options for treatment. Advances in our understanding of molecular and viral biology have caused many to look at viruses as potential modular biotherapeutics, where deleterious characteristics can be tamed and desirable characteristics exploited. In this article, we will explore both of these perspectives, covering how viral infections and involvement in microbiome dynamics may contribute to CRC, and examine ways in which viruses themselves could be harnessed to treat the very condition their contemporaries may have had a hand in creating.
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Affiliation(s)
| | - Ambarish C Varadan
- School of Natural Sciences, University of California Merced, Merced, CA, United States
| | - Shea F Grenier
- Department of Biology, San Diego State University, San Diego, CA, United States
| | - Juris A Grasis
- School of Natural Sciences, University of California Merced, Merced, CA, United States
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6
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Oncolytic Herpes Simplex Virus and PI3K Inhibitor BKM120 Synergize to Promote Killing of Prostate Cancer Stem-like Cells. MOLECULAR THERAPY-ONCOLYTICS 2019; 13:58-66. [PMID: 31016228 PMCID: PMC6468160 DOI: 10.1016/j.omto.2019.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 03/21/2019] [Indexed: 01/08/2023]
Abstract
Novel therapies to override chemo-radiation resistance in prostate cancer (PCa) are needed. Prostate cancer sphere-forming cells (PCSCs) (also termed prostate cancer stem-like cells) likely participate in tumor progression and recurrence, and they are important therapeutic targets. We established PCSC-enriched spheres by culturing human (DU145) and murine (TRAMP-C2) PCa cells in growth factor-defined serum-free medium, and we characterized stem-like properties of clonogenicity and tumorigenicity. The efficacy of two different oncolytic herpes simplex viruses (oHSVs) (G47Δ and MG18L) in PCSCs was tested alone and in combination with radiation; chemotherapy; and inhibitors of phosphoinositide 3-kinase (PI3K), Wnt, and NOTCH in vitro; and, G47Δ was tested with the PI3K inhibitor BKM120 in a PCSC-derived tumor model in vivo. PCSCs were more tumorigenic than serum-cultured parental cells. Human and murine PCSCs were sensitive to oHSV and BKM120 killing in vitro, while the combination was synergistic. oHSV combined with radiation, docetaxel, Wnt, or NOTCH inhibitors was not. In athymic mice bearing DU145 PCSC-derived tumors, the combination of intra-tumoral G47Δ and systemic BKM120 induced complete regression of tumors in 2 of 7 animals, and it exhibited superior anti-tumor activity compared to either monotherapy alone, with no detectable toxicity. oHSV synergizes with BKM120 in killing PCSCs in vitro, and the combination markedly inhibits tumor growth, even inducing regression in vivo.
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7
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Stern-Ginossar N, Thompson SR, Mathews MB, Mohr I. Translational Control in Virus-Infected Cells. Cold Spring Harb Perspect Biol 2019; 11:a033001. [PMID: 29891561 PMCID: PMC6396331 DOI: 10.1101/cshperspect.a033001] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
As obligate intracellular parasites, virus reproduction requires host cell functions. Despite variations in genome size and configuration, nucleic acid composition, and their repertoire of encoded functions, all viruses remain unconditionally dependent on the protein synthesis machinery resident within their cellular hosts to translate viral messenger RNAs (mRNAs). A complex signaling network responsive to physiological stress, including infection, regulates host translation factors and ribosome availability. Furthermore, access to the translation apparatus is patrolled by powerful host immune defenses programmed to restrict viral invaders. Here, we review the tactics and mechanisms used by viruses to appropriate control over host ribosomes, subvert host defenses, and dominate the infected cell translational landscape. These not only define aspects of infection biology paramount for virus reproduction, but continue to drive fundamental discoveries into how cellular protein synthesis is controlled in health and disease.
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Affiliation(s)
- Noam Stern-Ginossar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sunnie R Thompson
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Michael B Mathews
- Department of Medicine, Rutgers New Jersey Medical School, Newark, New Jersey 07103
| | - Ian Mohr
- Department of Microbiology, New York University School of Medicine, New York, New York 10016
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8
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Burgess HM, Pourchet A, Hajdu CH, Chiriboga L, Frey AB, Mohr I. Targeting Poxvirus Decapping Enzymes and mRNA Decay to Generate an Effective Oncolytic Virus. MOLECULAR THERAPY-ONCOLYTICS 2018; 8:71-81. [PMID: 29888320 PMCID: PMC5991893 DOI: 10.1016/j.omto.2018.01.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 01/12/2018] [Indexed: 12/20/2022]
Abstract
Through the action of two virus-encoded decapping enzymes (D9 and D10) that remove protective caps from mRNA 5′-termini, Vaccinia virus (VACV) accelerates mRNA decay and limits activation of host defenses. D9- or D10-deficient VACV are markedly attenuated in mice and fail to counter cellular double-stranded RNA-responsive innate immune effectors, including PKR. Here, we capitalize upon this phenotype and demonstrate that VACV deficient in either decapping enzyme are effective oncolytic viruses. Significantly, D9- or D10-deficient VACV displayed anti-tumor activity against syngeneic mouse tumors of different genetic backgrounds and human hepatocellular carcinoma xenografts. Furthermore, D9- and D10-deficient VACV hyperactivated the host anti-viral enzyme PKR in non-tumorigenic cells compared to wild-type virus. This establishes a new genetic platform for oncolytic VACV development that is deficient for a major pathogenesis determinant while retaining viral genes that support robust productive replication like those required for nucleotide metabolism. It further demonstrates how VACV mutants unable to execute a fundamental step in virus-induced mRNA decay can be unexpectedly translated into a powerful anti-tumor therapy.
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Affiliation(s)
- Hannah M Burgess
- Department of Microbiology, NYU School of Medicine, New York, NY, USA
| | - Aldo Pourchet
- Department of Microbiology, NYU School of Medicine, New York, NY, USA
| | - Cristina H Hajdu
- Department of Pathology, NYU School of Medicine, New York, NY, USA.,Laura and Isaac Perlmutter Cancer Center, NYU Langone Medical Center, New York, NY, USA
| | - Luis Chiriboga
- Department of Pathology, NYU School of Medicine, New York, NY, USA
| | - Alan B Frey
- Department of Cell Biology, NYU School of Medicine, New York, NY, USA.,Laura and Isaac Perlmutter Cancer Center, NYU Langone Medical Center, New York, NY, USA
| | - Ian Mohr
- Department of Microbiology, NYU School of Medicine, New York, NY, USA.,Laura and Isaac Perlmutter Cancer Center, NYU Langone Medical Center, New York, NY, USA
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9
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Pourchet A, Copin R, Mulvey MC, Shopsin B, Mohr I, Wilson AC. Shared ancestry of herpes simplex virus 1 strain Patton with recent clinical isolates from Asia and with strain KOS63. Virology 2017; 512:124-131. [PMID: 28957690 PMCID: PMC5653468 DOI: 10.1016/j.virol.2017.09.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 09/16/2017] [Accepted: 09/18/2017] [Indexed: 12/18/2022]
Abstract
Herpes simplex virus 1 (HSV-1) is a widespread pathogen that persists for life, replicating in surface tissues and establishing latency in peripheral ganglia. Increasingly, molecular studies of latency use cultured neuron models developed using recombinant viruses such as HSV-1 GFP-US11, a derivative of strain Patton expressing green fluorescent protein (GFP) fused to the viral US11 protein. Visible fluorescence follows viral DNA replication, providing a real time indicator of productive infection and reactivation. Patton was isolated in Houston, Texas, prior to 1973, and distributed to many laboratories. Although used extensively, the genomic structure and phylogenetic relationship to other strains is poorly known. We report that wild type Patton and the GFP-US11 recombinant contain the full complement of HSV-1 genes and differ within the unique regions at only eight nucleotides, changing only two amino acids. Although isolated in North America, Patton is most closely related to Asian viruses, including KOS63.
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Affiliation(s)
- Aldo Pourchet
- Department of Microbiology, New York University School of Medicine, New York, NY, USA
| | - Richard Copin
- Department of Medicine, New York University School of Medicine, New York, NY, USA
| | | | - Bo Shopsin
- Department of Microbiology, New York University School of Medicine, New York, NY, USA; Department of Medicine, New York University School of Medicine, New York, NY, USA
| | - Ian Mohr
- Department of Microbiology, New York University School of Medicine, New York, NY, USA
| | - Angus C Wilson
- Department of Microbiology, New York University School of Medicine, New York, NY, USA.
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10
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Ma Y, Chen M, Jin H, Prabhakar BS, Valyi-Nagy T, He B. An Engineered Herpesvirus Activates Dendritic Cells and Induces Protective Immunity. Sci Rep 2017; 7:41461. [PMID: 28150813 PMCID: PMC5288694 DOI: 10.1038/srep41461] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 12/19/2016] [Indexed: 01/30/2023] Open
Abstract
Herpes simplex viruses (HSV) are human pathogens that switch between lytic and latent infection. While attenuated HSV is explored for vaccine, the underlying event remains poorly defined. Here we report that recombinant HSV-1 with a mutation in the γ134.5 protein, a virulence factor, stimulates dendritic cell (DC) maturation which is dependent on TANK-binding kinase 1 (TBK1). When exposed to CD11+ DCs, the mutant virus that lacks the amino terminus of γ134.5 undergoes temporal replication without production of infectious virus. Mechanistically, this leads to sequential phosphorylation of interferon regulatory factor 3 (IRF3) and p65/RelA. In correlation, DCs up-regulate the expression of co-stimulatory molecules and cytokines. However, selective inhibition of TBK1 precludes phosphorylation of IRF3 and subsequent DC activation by the γ134.5 mutant. Herein, the γ134.5 mutant is immune-stimulatory and non-destructive to DCs. Remarkably, upon immunization the γ134.5 mutant induces protection against lethal challenge by the wild type virus, indicative of its vaccine potential. Furthermore, CD11+ DCs primed by the γ134.5 mutant in vivo mediate protection upon adoptive transfer. These results suggest that activation of TBK1 by engineered HSV is crucial for DC maturation, which may contribute to protective immunity.
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Affiliation(s)
- Yijie Ma
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Min Chen
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, Illinois, USA.,Institute of Viral Hepatitis, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010, China
| | - Huali Jin
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Bellur S Prabhakar
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Tibor Valyi-Nagy
- Department of Pathology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Bin He
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, Illinois, USA
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11
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Pourchet A, Fuhrmann SR, Pilones KA, Demaria S, Frey AB, Mulvey M, Mohr I. CD8(+) T-cell Immune Evasion Enables Oncolytic Virus Immunotherapy. EBioMedicine 2016; 5:59-67. [PMID: 27077112 PMCID: PMC4816761 DOI: 10.1016/j.ebiom.2016.01.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 01/08/2016] [Accepted: 01/15/2016] [Indexed: 12/28/2022] Open
Abstract
Although counteracting innate defenses allows oncolytic viruses (OVs) to better replicate and spread within tumors, CD8(+) T-cells restrict their capacity to trigger systemic anti-tumor immune responses. Herpes simplex virus-1 (HSV-1) evades CD8(+) T-cells by producing ICP47, which limits immune recognition of infected cells by inhibiting the transporter associated with antigen processing (TAP). Surprisingly, removing ICP47 was assumed to benefit OV immuno-therapy, but the impact of inhibiting TAP remains unknown because human HSV-1 ICP47 is not effective in rodents. Here, we engineer an HSV-1 OV to produce bovine herpesvirus UL49.5, which unlike ICP47, antagonizes rodent and human TAP. Significantly, UL49.5-expressing OVs showed superior efficacy treating bladder and breast cancer in murine models that was dependent upon CD8(+) T-cells. Besides injected subcutaneous tumors, UL49.5-OV reduced untreated, contralateral tumor size and metastases. These findings establish TAP inhibitor-armed OVs that evade CD8(+) T-cells as an immunotherapy strategy to elicit potent local and systemic anti-tumor responses.
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Affiliation(s)
- Aldo Pourchet
- Department of Microbiology, New York University School of Medicine, New York, NY, USA
| | | | - Karsten A. Pilones
- Department of Pathology, New York University School of Medicine, New York, NY, USA
| | - Sandra Demaria
- Department of Pathology, New York University School of Medicine, New York, NY, USA
- NYU Cancer Institute, New York University School of Medicine, New York, NY, USA
| | - Alan B. Frey
- Department of Cell Biology, New York University School of Medicine, New York, NY, USA
- NYU Cancer Institute, New York University School of Medicine, New York, NY, USA
| | | | - Ian Mohr
- Department of Microbiology, New York University School of Medicine, New York, NY, USA
- NYU Cancer Institute, New York University School of Medicine, New York, NY, USA
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12
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Kohlhapp FJ, Kaufman HL. Molecular Pathways: Mechanism of Action for Talimogene Laherparepvec, a New Oncolytic Virus Immunotherapy. Clin Cancer Res 2015; 22:1048-54. [PMID: 26719429 DOI: 10.1158/1078-0432.ccr-15-2667] [Citation(s) in RCA: 206] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 12/16/2015] [Indexed: 12/14/2022]
Abstract
Oncolytic viruses are native or engineered viruses that preferentially replicate in and lyse cancer cells. Selective tumor cell replication is thought to depend on infection of neoplastic cells, which harbor low levels of protein kinase R (PKR) and dysfunctional type I IFN signaling elements. These changes allow more efficient viral replication, and with selected deletion of specific viral genes, replication in normal cells with activated PKR may not be possible. Direct tumor cell lysis, release of soluble tumor antigens, and danger-associated molecular factors are all thought to help prime and promote tumor-specific immunity. Talimogene laherparepvec (T-VEC) is a genetically modified herpes simplex virus, type I and is the first oncolytic virus to demonstrate a clinical benefit in patients with melanoma. T-VEC has also been evaluated for the treatment of head and neck cancer, pancreatic cancer, and likely other types of cancer will be targeted in the near future. T-VEC has been modified for improved safety, tumor-selective replication, and induction of host immunity by deletion of several viral genes and expression of human granulocyte-macrophage colony stimulating factor. Although the mechanism of action for T-VEC is incompletely understood, the safety profile of T-VEC and ability to promote immune responses suggest future combination studies with other immunotherapy approaches including checkpoint blockade through PD-1, PD-L1, and CTLA-4 to be a high priority for clinical development. Oncolytic viruses also represent unique regulatory and biosafety challenges but offer a potential new class of agents for the treatment of cancer.
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Affiliation(s)
- Frederick J Kohlhapp
- Division of Surgical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey
| | - Howard L Kaufman
- Division of Surgical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey.
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13
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Sokolowski NA, Rizos H, Diefenbach RJ. Oncolytic virotherapy using herpes simplex virus: how far have we come? Oncolytic Virother 2015; 4:207-19. [PMID: 27512683 PMCID: PMC4918397 DOI: 10.2147/ov.s66086] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Oncolytic virotherapy exploits the properties of human viruses to naturally cytolysis of cancer cells. The human pathogen herpes simplex virus (HSV) has proven particularly amenable for use in oncolytic virotherapy. The relative safety of HSV coupled with extensive knowledge on how HSV interacts with the host has provided a platform for manipulating HSV to enhance the targeting and killing of human cancer cells. This has culminated in the approval of talimogene laherparepvec for the treatment of melanoma. This review focuses on the development of HSV as an oncolytic virus and where the field is likely to head in the future.
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Affiliation(s)
- Nicolas As Sokolowski
- Centre for Virus Research, Westmead Millennium Institute for Medical Research, The University of Sydney, NSW, Australia
| | - Helen Rizos
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, NSW, Australia
| | - Russell J Diefenbach
- Centre for Virus Research, Westmead Millennium Institute for Medical Research, The University of Sydney, NSW, Australia
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14
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Appleton ES, Turnbull S, Ralph C, West E, Scott K, Harrington K, Pandha H, Melcher A. Talimogene laherparepvec in the treatment of melanoma. Expert Opin Biol Ther 2015; 15:1517-30. [DOI: 10.1517/14712598.2015.1084280] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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15
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Peters C, Rabkin SD. Designing Herpes Viruses as Oncolytics. MOLECULAR THERAPY-ONCOLYTICS 2015; 2:S2372-7705(16)30012-2. [PMID: 26462293 PMCID: PMC4599707 DOI: 10.1038/mto.2015.10] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Oncolytic herpes simplex virus (oHSV) was one of the first genetically-engineered oncolytic viruses. Because herpes simplex virus (HSV) is a natural human pathogen that can cause serious disease, it is incumbent that it be genetically-engineered or significantly attenuated for safety. Here we present a detailed explanation of the functions of HSV-1 genes frequently mutated to endow oncolytic activity. These genes are non-essential for growth in tissue culture cells but are important for growth in post-mitotic cells, interfering with intrinsic antiviral and innate immune responses or causing pathology, functions dispensable for replication in cancer cells. Understanding the function of these genes leads to informed creation of new oHSVs with better therapeutic efficacy. Virus infection and replication can also be directed to cancer cells through tumor-selective receptor binding and transcriptional- or post-transcriptional miRNA-targeting, respectively. In addition to the direct effects of oHSV on infected cancer cells and tumors, oHSV can be 'armed' with transgenes that are: reporters, to track virus replication and spread; cytotoxic, to kill uninfected tumor cells; immune modulatory, to stimulate anti-tumor immunity; or tumor microenvironment altering, to enhance virus spread or to inhibit tumor growth. In addition to HSV-1, other alphaherpesviruses are also discussed for their oncolytic activity.
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Affiliation(s)
- Cole Peters
- Program in Virology, Harvard Medical School, Boston, MA, and Department of Neurosurgery, Massachusetts General Hospital and Harvard Medical School, Boston MA
| | - Samuel D Rabkin
- Program in Virology, Harvard Medical School, Boston, MA, and Department of Neurosurgery, Massachusetts General Hospital and Harvard Medical School, Boston MA
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16
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Wu X, Li Y, Wang J, Wen X, Marcus MT, Daniels G, Zhang DY, Ye F, Wang LH, Du X, Adams S, Singh B, Zavadil J, Lee P, Monaco ME. Long chain fatty Acyl-CoA synthetase 4 is a biomarker for and mediator of hormone resistance in human breast cancer. PLoS One 2013; 8:e77060. [PMID: 24155918 PMCID: PMC3796543 DOI: 10.1371/journal.pone.0077060] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 09/05/2013] [Indexed: 12/16/2022] Open
Abstract
The purpose of this study was to determine the role of long-chain fatty acyl-CoA synthetase 4 (ACSL4) in breast cancer. Public databases were utilized to analyze the relationship between ACSL4 mRNA expression and the presence of steroid hormone and human epidermal growth factor receptor 2 (HER2) in both breast cancer cell lines and tissue samples. In addition, cell lines were utilized to assess the consequences of either increased or decreased levels of ACSL4 expression. Proliferation, migration, anchorage-independent growth and apoptosis were used as biological end points. Effects on mRNA expression and signal transduction pathways were also monitored. A meta-analysis of public gene expression databases indicated that ACSL4 expression is positively correlated with a unique subtype of triple negative breast cancer (TNBC), characterized by the absence of androgen receptor (AR) and therefore referred to as quadruple negative breast cancer (QNBC). Results of experiments in breast cancer cell lines suggest that simultaneous expression of ACSL4 and a receptor is associated with hormone resistance. Forced expression of ACSL4 in ACSL4-negative, estrogen receptor α (ER)-positive MCF-7 cells resulted in increased growth, invasion and anchorage independent growth, as well as a loss of dependence on estrogen that was accompanied by a reduction in the levels of steroid hormone receptors. Sensitivity to tamoxifen, triacsin C and etoposide was also attenuated. Similarly, when HER2-positive, ACSL4-negative, SKBr3 breast cancer cells were induced to express ACSL4, the proliferation rate increased and the apoptotic effect of lapatinib was reduced. The growth stimulatory effect of ACSL4 expression was also observed in vivo in nude mice when MCF-7 control and ACSL4-expressing cells were utilized to induce tumors. Our data strongly suggest that ACSL4 can serve as both a biomarker for, and mediator of, an aggressive breast cancer phenotype.
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MESH Headings
- Animals
- Antineoplastic Agents/pharmacology
- Antineoplastic Agents/therapeutic use
- Apoptosis/drug effects
- Apoptosis/genetics
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/metabolism
- Breast Neoplasms/classification
- Breast Neoplasms/drug therapy
- Breast Neoplasms/enzymology
- Breast Neoplasms/genetics
- Cell Adhesion
- Cell Line, Tumor
- Cell Proliferation
- Coenzyme A Ligases/genetics
- Coenzyme A Ligases/metabolism
- Drug Resistance, Neoplasm/drug effects
- Drug Resistance, Neoplasm/genetics
- Estrogen Receptor alpha/genetics
- Estrogen Receptor alpha/metabolism
- Female
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic/drug effects
- Hormones/pharmacology
- Humans
- Mice
- Mice, Nude
- Neoplasm Invasiveness
- Oligonucleotide Array Sequence Analysis
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, ErbB-2/genetics
- Receptor, ErbB-2/metabolism
- Reproducibility of Results
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Affiliation(s)
- Xinyu Wu
- Department of Neuroscience & Physiology, New York University School of Medicine, New York, New York, United States of America
| | - Yirong Li
- Department of Pathology, New York University School of Medicine, New York, New York, United States of America
| | - Jinhua Wang
- Department of Pediatrics, New York University School of Medicine, New York, New York, United States of America
- NYU Cancer Institute, New York University School of Medicine, New York, New York, United States of America
- NYU Center for Health Informatics and Bioinformatics, New York University School of Medicine, New York, New York, United States of America
| | - Xin Wen
- Department of Pediatrics, New York University School of Medicine, New York, New York, United States of America
- NYU Cancer Institute, New York University School of Medicine, New York, New York, United States of America
- NYU Center for Health Informatics and Bioinformatics, New York University School of Medicine, New York, New York, United States of America
| | - Max T. Marcus
- Department of Neuroscience & Physiology, New York University School of Medicine, New York, New York, United States of America
| | - Garrett Daniels
- Department of Pathology, New York University School of Medicine, New York, New York, United States of America
| | - David Y. Zhang
- Department of Pathology, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Fei Ye
- Department of Pathology, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Ling Hang Wang
- Department of Pathology, New York University School of Medicine, New York, New York, United States of America
| | - Xinxin Du
- Department of Pathology, New York University School of Medicine, New York, New York, United States of America
| | - Sylvia Adams
- Department of Medicine, New York University School of Medicine, New York, New York, United States of America
- NYU Cancer Institute, New York University School of Medicine, New York, New York, United States of America
| | - Baljit Singh
- Department of Pathology, New York University School of Medicine, New York, New York, United States of America
- NYU Cancer Institute, New York University School of Medicine, New York, New York, United States of America
| | - Jiri Zavadil
- Department of Pathology, New York University School of Medicine, New York, New York, United States of America
- NYU Cancer Institute, New York University School of Medicine, New York, New York, United States of America
| | - Peng Lee
- Department of Pathology, New York University School of Medicine, New York, New York, United States of America
- NYU Cancer Institute, New York University School of Medicine, New York, New York, United States of America
- VA New York Harbor Healthcare System, New York, New York, United States of America
- *E-mail: (MM); (PL)
| | - Marie E. Monaco
- Department of Neuroscience & Physiology, New York University School of Medicine, New York, New York, United States of America
- NYU Cancer Institute, New York University School of Medicine, New York, New York, United States of America
- VA New York Harbor Healthcare System, New York, New York, United States of America
- *E-mail: (MM); (PL)
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17
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Walsh D, Mathews MB, Mohr I. Tinkering with translation: protein synthesis in virus-infected cells. Cold Spring Harb Perspect Biol 2013; 5:a012351. [PMID: 23209131 DOI: 10.1101/cshperspect.a012351] [Citation(s) in RCA: 178] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Viruses are obligate intracellular parasites, and their replication requires host cell functions. Although the size, composition, complexity, and functions encoded by their genomes are remarkably diverse, all viruses rely absolutely on the protein synthesis machinery of their host cells. Lacking their own translational apparatus, they must recruit cellular ribosomes in order to translate viral mRNAs and produce the protein products required for their replication. In addition, there are other constraints on viral protein production. Crucially, host innate defenses and stress responses capable of inactivating the translation machinery must be effectively neutralized. Furthermore, the limited coding capacity of the viral genome needs to be used optimally. These demands have resulted in complex interactions between virus and host that exploit ostensibly virus-specific mechanisms and, at the same time, illuminate the functioning of the cellular protein synthesis apparatus.
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Affiliation(s)
- Derek Walsh
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA.
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18
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Effect of γ34.5 deletions on oncolytic herpes simplex virus activity in brain tumors. J Virol 2012; 86:4420-31. [PMID: 22345479 DOI: 10.1128/jvi.00017-12] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The ICP34.5 protein of herpes simplex virus (HSV) is involved in many aspects of viral pathogenesis; promoting neurovirulence, inhibiting interferon-induced shutoff of protein synthesis, interacting with PCNA and TBK1, inhibiting dendritic cell (DC) maturation, and binding to Beclin 1 to interfere with autophagy. Because of its key role in neuropathogenicity, the γ34.5 gene is deleted in all oncolytic HSVs (oHSVs) currently in clinical trial for treating malignant gliomas. Unfortunately, deletion of γ34.5 attenuates virus replication in cancer cells, especially human glioblastoma stem cells (GSCs). To develop new oHSVs for use in the brain and that replicate in GSCs, we explored the effect of deleting the γ34.5 Beclin 1 binding domain (BBD). To ensure cancer selectivity and safety, we inactivated the ICP6 gene (UL39, large subunit of ribonucleotide reductase), constructing ICP6 mutants with different γ34.5 genotypes: Δ68HR-6, intact γ34.5; Δ68H-6, γ34.5 BBD deleted; and 1716-6, γ34.5 deleted. Multimutated Δ68H-6 exhibited minimal neuropathogenicity in HSV-1-susceptible mice, as opposed to Δ68H and Δ68HR-6. It replicated well in human glioma cell lines and GSCs, effectively killing cells in vitro and prolonging survival of mice bearing orthotopic brain tumors. In contrast, 1716 and 1716-6 barely replicated in GSCs. Infection of glioma cells with Δ68H-6 and 1716-6 induced autophagy and increased phosphorylation of eIF2α, while inhibition of autophagy, by Beclin 1 short hairpin RNA (shRNA) knockdown or pharmacological inhibition, had no effect on virus replication or phosphorylated eIF2α (p-eIF2α) levels. Thus, Δ68H-6 represents a new oHSV vector that is safe and effective against a variety of brain tumor models.
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Li Y, Ligr M, McCarron JP, Daniels G, Zhang D, Zhao X, Ye F, Wang J, Liu X, Osman I, Mencher SK, Lepor H, Wang LG, Ferrari A, Lee P. Natura-alpha targets forkhead box m1 and inhibits androgen-dependent and -independent prostate cancer growth and invasion. Clin Cancer Res 2011; 17:4414-24. [PMID: 21606178 DOI: 10.1158/1078-0432.ccr-11-0431] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE The development of new effective therapeutic agents with minimal side effects for prostate cancer (PC) treatment is much needed. Indirubin, an active molecule identified in the traditional Chinese herbal medicine-Qing Dai (Indigo naturalis), has been used to treat leukemia for decades. However, the anticancer properties of Natura-alpha, an indirubin derivative, are not well studied in solid tumors, particularly in PC. EXPERIMENTAL DESIGN The growth kinetics and invasion ability of on human PC cell lines with or without Natura-alpha treatment were measured by cell proliferation and invasion assays. The antitumor effects of Natura-alpha were examined in nude mice tumor xenograft models, and in a patient with advanced hormone-refractory metastatic PC. Signal network proteins targeted by Natura-alpha were analyzed by using proteomic pathway array analysis (PPAA) on xenografts. RESULTS Natura-alpha inhibited the growth of both androgen-dependent (LNCaP) and androgen-independent (LNCaP-AI, PC-3, and DU145) PC cells with IC(50) between 4 to 10 mmol/L, and also inhibited invasion of androgen-independent PC cells. Its antitumor effects were further evident in in vivo tumor reduction in androgen-dependent and androgen-independent nude mice tumor xenograft models and reduced tumor volume in the patient with hormone refractory metastatic PC. PPAA revealed that antiproliferative and antiinvasive activities of Natura-alpha on PC might primarily be through its downregulation of Forkhead box M1 (FOXM1) protein. Forced overexpression of FOXM1 largely reversed the inhibition of growth and invasion by Natura-alpha. CONCLUSION Natura-alpha could serve as a novel and effective therapeutic agent for treatment of both hormone-sensitive and hormone-refractory PC with minimal side effects.
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Affiliation(s)
- Yirong Li
- Department of Pathology, New York University School of Medicine, New York, New York, USA
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20
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Horst D, Ressing ME, Wiertz EJHJ. Exploiting human herpesvirus immune evasion for therapeutic gain: potential and pitfalls. Immunol Cell Biol 2011; 89:359-66. [PMID: 21301483 DOI: 10.1038/icb.2010.129] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Herpesviruses stand out for their capacity to establish lifelong infections of immunocompetent hosts, generally without causing overt symptoms. Herpesviruses are equipped with sophisticated immune evasion strategies, allowing these viruses to persist for life despite the presence of a strong antiviral immune response. Although viral evasion tactics appear to target virtually any stage of the innate and adaptive host immune response, detailed knowledge is now available on the molecular mechanisms underlying herpesvirus obstruction of MHC class I-restricted antigen presentation to T cells. This opens the way for clinical application. Here, we review and discuss recent efforts to exploit human herpesvirus MHC class I evasion strategies for the rational design of novel strategies for vaccine development, cancer treatment, transplant protection and gene therapy.
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Affiliation(s)
- Daniëlle Horst
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
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21
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Anesti AM, Simpson GR, Price T, Pandha HS, Coffin RS. Expression of RNA interference triggers from an oncolytic herpes simplex virus results in specific silencing in tumour cells in vitro and tumours in vivo. BMC Cancer 2010; 10:486. [PMID: 20836854 PMCID: PMC2944180 DOI: 10.1186/1471-2407-10-486] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Accepted: 09/13/2010] [Indexed: 12/31/2022] Open
Abstract
Background Delivery of small interfering RNA (siRNA) to tumours remains a major obstacle for the development of RNA interference (RNAi)-based therapeutics. Following the promising pre-clinical and clinical results with the oncolytic herpes simplex virus (HSV) OncoVEXGM-CSF, we aimed to express RNAi triggers from oncolytic HSV, which although has the potential to improve treatment by silencing tumour-related genes, was not considered possible due to the highly oncolytic properties of HSV. Methods To evaluate RNAi-mediated silencing from an oncolytic HSV backbone, we developed novel replicating HSV vectors expressing short-hairpin RNA (shRNA) or artificial microRNA (miRNA) against the reporter genes green fluorescent protein (eGFP) and β-galactosidase (lacZ). These vectors were tested in non-tumour cell lines in vitro and tumour cells that are moderately susceptible to HSV infection both in vitro and in mice xenografts in vivo. Silencing was assessed at the protein level by fluorescent microscopy, x-gal staining, enzyme activity assay, and western blotting. Results Our results demonstrate that it is possible to express shRNA and artificial miRNA from an oncolytic HSV backbone, which had not been previously investigated. Furthermore, oncolytic HSV-mediated delivery of RNAi triggers resulted in effective and specific silencing of targeted genes in tumour cells in vitro and tumours in vivo, with the viruses expressing artificial miRNA being comprehensibly more effective. Conclusions This preliminary data provide the first demonstration of oncolytic HSV-mediated expression of shRNA or artificial miRNA and silencing of targeted genes in tumour cells in vitro and in vivo. The vectors developed in this study are being adapted to silence tumour-related genes in an ongoing study that aims to improve the effectiveness of oncolytic HSV treatment in tumours that are moderately susceptible to HSV infection and thus, potentially improve response rates seen in human clinical trials.
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Affiliation(s)
- Anna-Maria Anesti
- Oncology Group, Postgraduate Medical School, University of Surrey, Surrey, GU2 5XH, UK
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22
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Marconi P, Argnani R, Epstein AL, Manservigi R. HSV as a vector in vaccine development and gene therapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 655:118-44. [PMID: 20047039 DOI: 10.1007/978-1-4419-1132-2_10] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The very deep knowledge acquired on the genetics and molecular biology of herpes simplex virus (HSV), major human pathogen whose lifestyle is based on a long-term dual interaction with the infected host characterized by the existence of lytic and latent infections, has allowed the development of potential vectors for several applications in human healthcare. These include delivery and expression of human genes to cells of the nervous system, selective destruction of cancer cells, prophylaxis against infection with HSV or other infectious diseases and targeted infection of specific tissues or organs. Three different classes of vectors can be derived from HSV-1: replication-competent attenuated vectors, replication-incompetent recombinant vectors and defective helper-dependent vectors known as amplicons. This chapter highlights the current knowledge concerning design, construction and recent applications, as well as the potential and current limitations of the three different classes of HSV-1-based vectors.
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Affiliation(s)
- Peggy Marconi
- Department of Experimental and Diagnostic Medicine-Section of Microbiology, University of Ferrara, Via Luigi Borsari 46, Ferrara, 44100, Italy.
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23
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Abstract
The very deep knowledge acquired on the genetics and molecular biology of herpes simplex virus (HSV), has allowed the development of potential replication-competent and replication-defective vectors for several applications in human healthcare. These include delivery and expression of human genes to cells of the nervous systems, selective destruction of cancer cells, prophylaxis against infection with HSV or other infectious diseases, and targeted infection to specific tissues or organs. Replication-defective recombinant vectors are non-toxic gene transfer tools that preserve most of the neurotropic features of wild type HSV-1, particularly the ability to express genes after having established latent infections, and are thus proficient candidates for therapeutic gene transfer settings in neurons. A replication-defective HSV vector for the treatment of pain has recently entered in phase 1 clinical trial. Replication-competent (oncolytic) vectors are becoming a suitable and powerful tool to eradicate brain tumours due to their ability to replicate and spread only within the tumour mass, and have reached phase II/III clinical trials in some cases. The progress in understanding the host immune response induced by the vector is also improving the use of HSV as a vaccine vector against both HSV infection and other pathogens. This review briefly summarizes the obstacle encountered in the delivery of HSV vectors and examines the various strategies developed or proposed to overcome such challenges.
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Affiliation(s)
- Roberto Manservigi
- Department of Experimental and Diagnostic Medicine - Section of Microbiology, University of Ferrara, Via Luigi Borsari 46, 44100 Ferrara, Italy
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24
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Manservigi R, Argnani R, Marconi P. HSV Recombinant Vectors for Gene Therapy. Open Virol J 2010; 4:123-56. [PMID: 20835362 DOI: 10.2174/1874357901004030123] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 03/13/2010] [Accepted: 03/31/2010] [Indexed: 12/16/2022] Open
Abstract
The very deep knowledge acquired on the genetics and molecular biology of herpes simplex virus (HSV), has allowed the development of potential replication-competent and replication-defective vectors for several applications in human healthcare. These include delivery and expression of human genes to cells of the nervous systems, selective destruction of cancer cells, prophylaxis against infection with HSV or other infectious diseases, and targeted infection to specific tissues or organs. Replication-defective recombinant vectors are non-toxic gene transfer tools that preserve most of the neurotropic features of wild type HSV-1, particularly the ability to express genes after having established latent infections, and are thus proficient candidates for therapeutic gene transfer settings in neurons. A replication-defective HSV vector for the treatment of pain has recently entered in phase 1 clinical trial. Replication-competent (oncolytic) vectors are becoming a suitable and powerful tool to eradicate brain tumours due to their ability to replicate and spread only within the tumour mass, and have reached phase II/III clinical trials in some cases. The progress in understanding the host immune response induced by the vector is also improving the use of HSV as a vaccine vector against both HSV infection and other pathogens. This review briefly summarizes the obstacle encountered in the delivery of HSV vectors and examines the various strategies developed or proposed to overcome such challenges.
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Affiliation(s)
- Roberto Manservigi
- Department of Experimental and Diagnostic Medicine - Section of Microbiology, University of Ferrara, Via Luigi Borsari 46, 44100 Ferrara, Italy
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25
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Development of a regulatable oncolytic herpes simplex virus type 1 recombinant virus for tumor therapy. J Virol 2010; 84:8163-71. [PMID: 20519407 DOI: 10.1128/jvi.00059-10] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Oncolytic viruses are genetically modified viruses that preferentially replicate in host cancer cells, leading to the production of new viruses and, ultimately, cell death. Currently, no oncolytic viruses that are able to kill only tumor cells while leaving normal cells intact are available. Using T-REx (Invitrogen, Carlsbad, CA) gene switch technology and a self-cleaving ribozyme, we have constructed a novel oncolytic HSV-1 recombinant, KTR27, whose replication can be tightly controlled and regulated by tetracycline in a dose-dependent manner. Infection of normal replicating cells as well as multiple human cancer cell types with KTR27 in the presence of tetracycline led to 1,000- to 250,000-fold-higher progeny virus production than in the absence of tetracycline, while little viral replication and virus-associated cytotoxicity was observed in infected growth-arrested normal human cells. We show that intratumoral inoculation with KTR27 markedly inhibits tumor growth in a xenograft model of human non-small-cell lung cancer in nude mice. It is shown further that replication of KTR27 in the inoculated tumors can be efficiently controlled by local codelivery of tetracycline to the target tumors at the time of KTR27 inoculation. Collectively, KTR27 possesses a unique pharmacological feature that can limit its replication to the targeted tumor microenvironment with localized tetracycline delivery, thus minimizing unwanted viral replication in distant tissues following local virotherapy. This regulatory mechanism would also allow the replication of the virus to be quickly shut down should adverse effects be detected.
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26
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Goetz C, Gromeier M. Preparing an oncolytic poliovirus recombinant for clinical application against glioblastoma multiforme. Cytokine Growth Factor Rev 2010; 21:197-203. [PMID: 20299272 DOI: 10.1016/j.cytogfr.2010.02.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
PVS-RIPO is a genetically recombinant, non-pathogenic poliovirus chimera with a tumor-specific conditional replication phenotype. Consisting of the genome of the live attenuated poliovirus type 1 (Sabin) vaccine with its cognate IRES element replaced with that of human rhinovirus type 2, PVS-RIPO displays an inability to translate its genome in untransformed neuronal cells, but effectively does so in cells originating from primary tumors in the central nervous system or other cancers. Hence, PVS-RIPO unleashes potent cytotoxic effects on infected cancer cells and produces sustained anti-tumoral responses in animal tumor models. PVS-RIPO presents a novel approach to the treatment of patients with glioblastoma multiforme, based on conditions favoring an unconventional viral translation initiation mechanism in cancerous cells. In this review we summarize advances in the understanding of major molecular determinants of PVS-RIPO oncolytic efficacy and safety and discuss their implications for upcoming clinical investigations.
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Affiliation(s)
- Christian Goetz
- Division of Neurosurgery, Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
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27
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Shah AC, Parker JN, Shimamura M, Cassady KA. Spontaneous and Engineered Compensatory HSV Mutants that Counteract the Host Antiviral PKR Response. Viruses 2009; 1:510-22. [PMID: 21994558 PMCID: PMC3185541 DOI: 10.3390/v1030510] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Revised: 10/22/2009] [Accepted: 10/22/2009] [Indexed: 01/25/2023] Open
Abstract
A virulent recombinant HSV lacking the diploid γ134.5 gene (Δγ134.5) have been investigated over the last two decades both for anti-tumor therapy and as vaccine vectors. The first generation vectors, while safe, are incapable of sustained replication in the majority of treated patients. An interferon inducible host antiviral kinase, protein kinase R (PKR), limits late viral protein synthesis and replication of Δγ134.5 viruses. This review describes the development of new Δγ134.5 vectors, through serial passage selection and direct viral genome engineering, which demonstrate selective PKR evasion in targeted cells and improved viral replication without restoring neurovirulence.
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Affiliation(s)
- Amish C. Shah
- University of Pennsylvania, Department of Pediatrics, Children’s Hospital of Philadelphia, 34 Street and Civic Center Boulevard, Philadelphia, PA 19104-4399, USA; E-Mail: (A.C.S.)
| | - Jacqueline N. Parker
- University of Alabama at Birmingham, Department of Pediatrics, Division of Infectious Disease, 1600 6th Avenue South, CHB 118C, Birmingham, AL 35222, USA; E-Mails: (J.N.P.); (M.S.)
| | - Masako Shimamura
- University of Alabama at Birmingham, Department of Pediatrics, Division of Infectious Disease, 1600 6th Avenue South, CHB 118C, Birmingham, AL 35222, USA; E-Mails: (J.N.P.); (M.S.)
| | - Kevin A. Cassady
- University of Alabama at Birmingham, Department of Pediatrics, Division of Infectious Disease, 1600 6th Avenue South, CHB 118C, Birmingham, AL 35222, USA; E-Mails: (J.N.P.); (M.S.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-205-996-7910; Fax: +1-205-934-0460
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28
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A let-7 MicroRNA-sensitive vesicular stomatitis virus demonstrates tumor-specific replication. Mol Ther 2008; 16:1437-43. [PMID: 18560417 DOI: 10.1038/mt.2008.130] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Creation of potent oncolytic viruses (OVs) suitable for the clinic may require new strategies in virus design. Replication-competent viruses facilitate a variety of approaches to achieving tumor specificity. Altered expression of microRNAs is a common hallmark of cancer that we demonstrate can be used to alter expression of a potent wild-type viral gene to achieve tumor-specific replication of an engineered vesicular stomatitis virus (VSV). Incorporation of let-7 microRNA complementary sequences within VSV eliminates undesirable replication and associated toxicity in normal cells but permits growth in cancer cells in vitro and in vivo. This is proof of concept that viruses designed to exploit the differential microRNA expression in cancer cells is a viable approach, potentially useful in optimizing oncolytic viral gene expression for maximal antitumor activity and safety.
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29
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Han ZQ, Assenberg M, Liu BL, Wang YB, Simpson G, Thomas S, Coffin RS. Development of a second-generation oncolytic Herpes simplex virus expressing TNFalpha for cancer therapy. J Gene Med 2007; 9:99-106. [PMID: 17256802 DOI: 10.1002/jgm.999] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Tumour necrosis factor alpha (TNFalpha) therapy is a promising anti-cancer treatment when combined with radiotherapy due to its potent radio sensitising effects, but systemic toxicity has limited its clinical use. Previously, non-replicative adenovirus vectors have been used to deliver TNFalpha directly to the tumour, including under the control of a radiation sensitive promoter. Here, we have used an ICP34.5 deleted, oncolytic herpes simplex virus (HSV) for delivery to increase expression levels and spread through the tumour, and the use of the US11 true late HSV promoter to limit expression to where the virus replicates, i.e. selectively in tumour tissue. METHODS TNFalpha expression under the CMV or US11 promoter was compared on cell lines CT26, BHK and Fadu. To further compare the activities of the promoters, expression of human TNFalpha was analysed in the presence and absence of acyclovir--an inhibitor of viral DNA replication and on HSV/ICP34.5- non-permissive cell line 3T6. The in vivo efficacy and toxicity of TNFalpha viruses were compared using A20 double flank tumour model in Balb/C mice and Fadu tumour model in nude mice. RESULTS The results demonstrated that the US11 promoter significantly reduced and delayed TNFalpha expression as compared to use of the CMV promoter, especially in non-permissive cells or in the presence of acyclovir. Despite the reduced and more selective expression levels, US11 driven TNFalpha showed improved anti-tumour effects compared to CMV driven TNFalpha, and without the toxic side effects. CONCLUSIONS This approach is therefore beneficial in increasing localised TNFalpha expression as compared to the use of non-replicative approaches, and combines the effects of TNFalpha with oncolytic virus replication which is expected to further enhance the efficacy of radiotherapy in a combined treatment approach.
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Affiliation(s)
- Z Q Han
- Biovex Ltd., 70 Milton Park, Abingdon, Oxon OX14 4RX, UK
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30
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Shah AC, Parker JN, Gillespie GY, Lakeman FD, Meleth S, Markert JM, Cassady KA. Enhanced antiglioma activity of chimeric HCMV/HSV-1 oncolytic viruses. Gene Ther 2007; 14:1045-54. [PMID: 17429445 DOI: 10.1038/sj.gt.3302942] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Oncolytic herpes simplex virus (HSV)-1 gamma(1)34.5-deletion mutants (Deltagamma(1)34.5 HSV) are promising agents for tumor therapy. The attenuating mutation renders the virus aneurovirulent but also limits late viral protein synthesis and efficient replication in many tumors. We tested whether one function of gamma(1)34.5 gene, which mediates late viral protein synthesis through host protein kinase R (PKR) antiviral response evasion, could be restored, without restoring the neurovirulence. We have previously reported the construction of two chimeric Deltagamma(1)34.5 HSV vectors (chimeric HSV), C130 and C134, which express the human cytomegalovirus (HCMV) PKR-evasion genes TRS1 and IRS1, respectively. We now demonstrate the following. The HCMV/HSV-1 chimeric viruses (i) maintain late viral protein synthesis in the human malignant glioma cells tested (D54-MG, U87-MG and U251-MG); (ii) replicate to higher titers than Deltagamma(1)34.5 HSV in malignant glioma cells in vitro and in vivo; (iii) are aneurovirulent; and (iv) are superior to other Deltagamma(1)34.5 HSV with both improved reduction of tumor volumes in vivo, and improved survival in two experimental murine brain tumor models. These findings demonstrate that transfer of HCMV IRS1 or TRS1 gene into Deltagamma(1)34.5 HSV significantly improves replication in malignant gliomas without restoring wild-type neurovirulence, resulting in enhanced tumor reduction and prolonged survival.
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Affiliation(s)
- A C Shah
- Department of Physiology and Biophysics, University of Alabama at Birmingham, Birmingham, AL 35233, USA
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31
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Vähä-Koskela MJ, Heikkilä JE, Hinkkanen AE. Oncolytic viruses in cancer therapy. Cancer Lett 2007; 254:178-216. [PMID: 17383089 PMCID: PMC7126325 DOI: 10.1016/j.canlet.2007.02.002] [Citation(s) in RCA: 220] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Revised: 02/01/2007] [Accepted: 02/05/2007] [Indexed: 12/26/2022]
Abstract
Oncolytic virotherapy is a promising form of gene therapy for cancer, employing nature’s own agents to find and destroy malignant cells. The purpose of this review is to provide an introduction to this very topical field of research and to point out some of the current observations, insights and ideas circulating in the literature. We have strived to acknowledge as many different oncolytic viruses as possible to give a broader picture of targeting cancer using viruses. Some of the newest additions to the panel of oncolytic viruses include the avian adenovirus, foamy virus, myxoma virus, yaba-like disease virus, echovirus type 1, bovine herpesvirus 4, Saimiri virus, feline panleukopenia virus, Sendai virus and the non-human coronaviruses. Although promising, virotherapy still faces many obstacles that need to be addressed, including the emergence of virus-resistant tumor cells.
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Affiliation(s)
- Markus J.V. Vähä-Koskela
- Åbo Akademi University, Department of Biochemistry and Pharmacy and Turku Immunology Centre, Turku, Finland
- Turku Graduate School of Biomedical Sciences, Turku, Finland
- Corresponding author. Address: Åbo Akademi University, Department of Biochemistry and Pharmacy and Turku Immunology Centre, Turku, Finland. Tel.: +358 2 215 4018; fax: +358 2 215 4745.
| | - Jari E. Heikkilä
- Åbo Akademi University, Department of Biochemistry and Pharmacy and Turku Immunology Centre, Turku, Finland
| | - Ari E. Hinkkanen
- Åbo Akademi University, Department of Biochemistry and Pharmacy and Turku Immunology Centre, Turku, Finland
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32
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Yang S, Guo ZS, O'Malley ME, Yin X, Zeh HJ, Bartlett DL. A new recombinant vaccinia with targeted deletion of three viral genes: its safety and efficacy as an oncolytic virus. Gene Ther 2007; 14:638-47. [PMID: 17268533 DOI: 10.1038/sj.gt.3302914] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To enhance further the safety and efficacy of oncolytic vaccinia virus, we have developed a new virus with targeted deletions of three viral genes encoding thymidine kinase and antiapoptotic/host range proteins SPI-1 and SPI-2 (vSPT). Infection of human and murine tumor cell lines yielded nearly equivalent or a log lower virus recovery in comparison to parental viruses. Viral infection activated multiple caspases in cancer cells but not in normal cells, suggesting infected cells may die via different pathways. In tumor-bearing mice, vSPT recovery from MC38 tumor was slightly reduced in comparison to two parental viruses. However, no virus was recovered from the brains and livers of mice injected with vSPT in contrast to control viruses. vSPT demonstrated significantly lower pathogenicity in nude mice. Systemic delivery of vSPT showed significant tumor inhibition in subcutaneous MC38 tumor, human ovarian A2780 and murine ovarian MOSEC carcinomatosis models; however, the tumor inhibition by vSPT was reduced compared with parental viruses. These results demonstrated that although deletion of these three viral genes further enhanced tumor selectivity, it also weakened the oncolytic potency. This study illustrates the complexity of creating a tumor-selective oncolytic virus by deleting multiple viral genes involved in multiple cellular pathways.
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Affiliation(s)
- S Yang
- University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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33
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Kanai R, Eguchi K, Takahashi M, Goldman S, Okano H, Kawase T, Yazaki T. Enhanced therapeutic efficacy of oncolytic herpes vector G207 against human non-small cell lung cancer--expression of an RNA-binding protein, Musashi1, as a marker for the tailored gene therapy. J Gene Med 2007; 8:1329-40. [PMID: 16955534 DOI: 10.1002/jgm.965] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Oncolytic herpes vectors like G207 have shown considerable promise in the treatment of solid tumors, but their potency must be enhanced for the full achievement of therapeutic efficacy. Deletion of the innate gamma34.5 gene made these vectors extremely safe, but their efficacy was also severely attenuated. Use of tumor-specific promoters is one method to direct toxicity and enhance efficacy against tumors. Recently, Musashi1 has been shown expressed in some tumor tissues. METHODS Eleven human cancer cell lines including five non-small cell lung cancers (NSCLCs) were investigated. Musashi1 mRNA expression was examined by RT-PCR analysis. Western blotting was also performed. Transcriptional activity of P/musashi1 in NSCLCs was assayed by GFP reporter plasmids. Then we constructed a defective amplicon vector containing musashi1 promoter/ICP34.5 with G207 as helper virus (dvM345). In vitro cytotoxicity against NSCLCs and growth characteristics of helper virus were examined. A Lu-99 subcutaneous tumor model was used in an animal study. The tumor volume treated with G207 alone or dvM345 was measured. RESULTS Musashi1 mRNA was detected in four cell lines. Two in five NSCLCs were positive, and P/musashi1 was proved functional within them. Against these cell lines, dvM345 showed enhanced cytotoxicity, and helper viral growth was augmented. A subcutaneous tumor study confirmed the enhanced therapeutic efficacy of G207 by dvM345 without compromising safety. CONCLUSIONS These results suggest that Musashi1 might be involved in the development of several carcinomas including NSCLC. In the context of oncolytic herpes vector strategy, the P/musashi1-ICP34.5 method could be used for the treatment of cancers expressing Musashi1.
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MESH Headings
- Animals
- Base Sequence
- Biomarkers, Tumor/genetics
- Carcinoma, Non-Small-Cell Lung/genetics
- Carcinoma, Non-Small-Cell Lung/metabolism
- Carcinoma, Non-Small-Cell Lung/therapy
- Cell Line, Tumor
- Female
- Genetic Therapy/methods
- Genetic Vectors
- Humans
- Lung Neoplasms/genetics
- Lung Neoplasms/metabolism
- Lung Neoplasms/therapy
- Mice
- Mice, Nude
- Neoplasm Transplantation
- Nerve Tissue Proteins/genetics
- Oncolytic Virotherapy/methods
- Oncolytic Viruses/genetics
- Promoter Regions, Genetic
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Neoplasm/genetics
- RNA, Neoplasm/metabolism
- RNA-Binding Proteins/genetics
- Transplantation, Heterologous
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Affiliation(s)
- Ryuichi Kanai
- Molecular Neurosurgery Laboratory, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
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Hu JC, Booth MJ, Tripuraneni G, Davies D, Zaidi SAA, Tamburo de Bella M, Slade MJ, Marley SB, Gordon MYA, Coffin RS, Coombes RC, Kamalati T. A Novel HSV-1 Virus, JS1/34.5−/47−, Purges Contaminating Breast Cancer Cells From Bone Marrow. Clin Cancer Res 2006; 12:6853-62. [PMID: 17121907 DOI: 10.1158/1078-0432.ccr-06-1228] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Oncolytic herpes simplex virus type 1 (HSV-1) vectors show considerable promise as agents for cancer therapy. We have developed a novel recombinant HSV-1 virus (JS1/34.5-/47-) for purging of occult breast cancer cells from bone marrow of patients. Here, we evaluate the therapeutic efficacy of this oncolytic virus. EXPERIMENTAL DESIGN Electron microscopy was used to determine whether human breast cancer and bone marrow cells are permissive for JS1/34.5-/47- infection. Subsequently, the biological effects of JS1/34.5-/47- infection on human breast cancer cells and bone marrow were established using cell proliferation and colony formation assays, and the efficiency of cell kill was evaluated. Finally, the efficiency of JS1/34.5-/47- purging of breast cancer cells was examined in cocultures of breast cancer cells with bone marrow as well as bone marrow samples from high-risk breast cancer patients. RESULTS We show effective killing of human breast cancer cell lines with the JS1/34.5-/47- virus. Furthermore, we show that treatment with JS1/34.5-/47- can significantly inhibit the growth of breast cancer cell lines without affecting cocultured mononuclear hematopoietic cells. Finally, we have found that the virus is effective in destroying disseminated tumors cells in bone marrow taken from breast cancer patients, without affecting the hematopoietic contents in these samples. CONCLUSION Collectively, our data show that the JS1/34.5-/47- virus can selectively target breast cancer cells while sparing hematopoietic cells, suggesting that JS1/34.5-/47- can be used to purge contaminating breast cancer cells from human bone marrow in the setting of autologous hematopoietic cell transplantation.
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Affiliation(s)
- Jennifer C Hu
- Department of Oncology, Cancer Cell Biology Section, Imperial College Faculty of Medicine, University College London, UK
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35
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Campbell SA, Mulvey M, Mohr I, Gromeier M. Attenuation of herpes simplex virus neurovirulence with picornavirus cis-acting genetic elements. J Virol 2006; 81:791-9. [PMID: 17079296 PMCID: PMC1797477 DOI: 10.1128/jvi.00714-06] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Viral pathogenesis depends on a suitable milieu in target host cells permitting viral gene expression, propagation, and spread. In many instances, viral genomes can be manipulated to select for propagation in certain tissues or cell types. This has been achieved for the neurotropic poliovirus (PV) by exchange of the internal ribosomal entry site (IRES), which is responsible for translation of the uncapped plus-strand RNA genome. The IRES of human rhinovirus type 2 (HRV2) confers neuron-specific replication deficits to PV but has no effect on viral propagation in malignant glioma cells. We report here that placing the critical gamma(1)34.5 virulence genes of herpes simplex virus type 1 (HSV) under translation control of the HRV2 IRES results in neuroattenuation in mice. In contrast, IRES insertion permits HSV propagation in malignant glioma cell lines that do not support replication of HSV recombinants carrying gamma(1)34.5 deletions. Our observations indicate that the conditions for alternative translation initiation at the HRV2 IRES in malignant glioma cells differ from those in normal central nervous system (CNS) cells. Picornavirus regulatory sequences mediating cell type-specific gene expression in the CNS can be utilized to target cancerous cells at the level of translation regulation outside their natural context.
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Affiliation(s)
- Stephanie A Campbell
- Division of Neurological Surgery, Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA
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36
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Shah AC, Price KH, Parker JN, Samuel SL, Meleth S, Cassady KA, Gillespie GY, Whitley RJ, Markert JM. Serial passage through human glioma xenografts selects for a Deltagamma134.5 herpes simplex virus type 1 mutant that exhibits decreased neurotoxicity and prolongs survival of mice with experimental brain tumors. J Virol 2006; 80:7308-15. [PMID: 16840311 PMCID: PMC1563698 DOI: 10.1128/jvi.00725-06] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Previous studies have described in vitro serial passage of a Deltagamma(1)34.5 herpes simplex virus type 1 (HSV-1) strain in SK-N-SH neuroblastoma cells and selection of mutants that have acquired the ability to infect and replicate in this previously nonpermissive cell line. Here we describe the selection of a mutant HSV-1 strain by in vivo serial passage, which prolongs survival in two separate experimental murine brain tumor models. Two conditionally replication-competent Deltagamma(1)34.5 viruses, M002, which expresses murine interleukin-12, and its parent virus, R3659, were serially passaged within human malignant glioma D54-MG cell lines in vitro or flank tumor xenografts in vivo. The major findings are (i) viruses passaged in vivo demonstrate decreased neurovirulence, whereas those passaged in vitro demonstrate a partial recovery of the neurovirulence associated with HSV-1; and (ii) vvD54-M002, the virus selected after in vivo serial passage of M002 in D54-MG tumors, improves survival in two independent murine brain tumor models compared to the parent (unpassaged) M002. Additionally, in vitro-passaged, but not in vivo-passaged, M002 displayed changes in the protein synthesis profile in previously nonpermissive cell lines, as well as early U(S)11 transcription. Thus, a mutant HSV-1 strain expressing a foreign gene can be selected for enhanced antitumor efficacy via in vivo serial passage within flank D54-MG tumor xenografts. The enhanced antitumor efficacy of vvD54-M002 is not due to restoration of protein synthesis or early U(S)11 expression. This finding emphasizes the contribution of the in vivo tumor environment for selecting novel oncolytic HSV specifically adapted for tumor cell destruction in vivo.
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Affiliation(s)
- Amish C Shah
- Division of Neurosurgery, University of Alabama at Birmingham, 510 20th Street South, Birmingham, AL 35294-3410, USA
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37
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Kanai R, Tomita H, Shinoda A, Takahashi M, Goldman S, Okano H, Kawase T, Yazaki T. Enhanced therapeutic efficacy of G207 for the treatment of glioma through Musashi1 promoter retargeting of gamma34.5-mediated virulence. Gene Ther 2006; 13:106-16. [PMID: 16163378 DOI: 10.1038/sj.gt.3302636] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
G207 is a conditionally replicating derivative of herpes simplex virus type1 (HSV-1) engineered with deletions of both ICP34.5 loci and a lacZ insertion disabling the ICP6 gene. G207 exhibits an efficient oncolytic activity in vitro and in vivo, yet minimal toxicity in normal tissue, and is now in clinical trial for malignant glioma. According to the results of clinical trials, however, although G207 was proved to be safe, the efficacy was not so impressive. Deletion of the ICP34.5 gene coding for virulence made G207 extremely safe, but it markedly reduced the cytotoxicity mediated by HSV-1. To enhance the therapeutic efficacy of G207 without diminishing its safety, we used a defective vector containing Musashi1 promoter/ICP34.5, with G207 as helper virus. P/musashi1 was functional selectively in human glioma cell lines (U87MG, U251, T98G) in this study and dvM345 showed a much higher therapeutic efficacy both in culture and in the in vivo glioma model, than G207 alone, without diminishing its favorable toxicity profile. These results suggest that transcriptional regulation of ICP34.5 by P/musashi1 can be used to target HSV-1 virulence toward gliomas while maintaining the desirable neuroattenuated phenotype.
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Affiliation(s)
- R Kanai
- Molecular Neurosurgery Laboratory, School of Medicine, Keio University, Tokyo, Japan
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38
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Naito S, Obayashi S, Sumi T, Iwai S, Nakazawa M, Ikuta K, Yura Y. Enhancement of antitumor activity of herpes simplex virus gamma(1)34.5-deficient mutant for oral squamous cell carcinoma cells by hexamethylene bisacetamide. Cancer Gene Ther 2006; 13:780-91. [PMID: 16645620 DOI: 10.1038/sj.cgt.7700957] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Current oncolytic viruses exert only limited antitumor activity on their own. There is a need to increase their oncolytic capability. We evaluated the effect of a differentiating reagent, hexamethylene bisacetamide (HMBA), on the antitumor activity of a gamma(1)34.5-deficient herpes simplex virus type 1 (HSV-1) R849 for human oral squamous cell carcinoma (SCC) cells. Hexamethylene bisacetamide increased the viral yield, especially at a low input multiplicity of infection (MOI), and the transcription of immediate early genes of HSV-1. Hexamethylene bisacetamide treatment promoted the cytopathic effect of R849 and increased the proportion of dead cells. Hexamethylene bisacetamide produced more apoptotic cells in R849-infected cells as compared with parental HSV-1(F)-infected cells. The growth of oral SCC xenografts in nude mice was markedly suppressed by treatment with R849 in combination with HMBA, and the survival of the co-treated animals was significantly prolonged as compared with that of animals treated with R849 only. Herpes simplex virus type 1 mRNA was expressed in tumors and trigeminal neurons, but not in brain, lung, liver, and kidney. These results indicate that HMBA enhances the antitumor activity of R849 through the expression of immediate early genes without increasing its toxicity. Hexamethylene bisacetamide can be used as an enhancing agent for oncolytic therapy with HSV-1 mutants.
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Affiliation(s)
- S Naito
- Department of Oral and Maxillofacial Surgery II, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan
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39
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Abstract
Cancer remains a serious threat to human health, causing over 500 000 deaths each year in US alone, exceeded only by heart diseases. Many new technologies are being developed to fight cancer, among which are gene therapies and oncolytic virotherapies. Herpes simplex virus type 1 (HSV-1) is a neurotropic DNA virus with many favorable properties both as a delivery vector for cancer therapeutic genes and as a backbone for oncolytic viruses. Herpes simplex virus type 1 is highly infectious, so HSV-1 vectors are efficient vehicles for the delivery of exogenous genetic materials to cells. The inherent cytotoxicity of this virus, if harnessed and made to be selective by genetic manipulations, makes this virus a good candidate for developing viral oncolytic approach. Furthermore, its large genome size, ability to infect cells with a high degree of efficiency, and the presence of an inherent replication controlling mechanism, the thymidine kinase gene, add to its potential capabilities. This review briefly summarizes the biology of HSV-1, examines various strategies that have been used to genetically modify the virus, and discusses preclinical as well as clinical results of the HSV-1-derived vectors in cancer treatment.
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Affiliation(s)
- Y Shen
- Mary Crowley Medical Research Center, Dallas, TX 75201, USA
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40
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Argnani R, Lufino M, Manservigi M, Manservigi R. Replication-competent herpes simplex vectors: design and applications. Gene Ther 2006; 12 Suppl 1:S170-7. [PMID: 16231051 DOI: 10.1038/sj.gt.3302622] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Replication-competent vectors are derived from attenuated viruses whose genes, that are nonessential for replication in cultured cells in vitro, are either mutated or deleted. The removal of one or more nonessential genes may reduce pathogenicity without requiring a cell line to complement growth. Herpes simplex viruses (HSV) are potential vectors for several applications in human healthcare. These include delivery and expression of human genes to cells of the nervous systems, selective destruction of cancer cells, prophylaxis against infection with HSV or other infectious diseases, and targeted infection to specific tissues or organs. This review highlights the progress in creating attenuated genetically engineered HSV vectors.
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Affiliation(s)
- R Argnani
- Department of Experimental and Diagnostic Medicine, Section of Microbiology, University of Ferrara, Ferrara, Italy
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41
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Mohr I. To replicate or not to replicate: achieving selective oncolytic virus replication in cancer cells through translational control. Oncogene 2005; 24:7697-709. [PMID: 16299530 DOI: 10.1038/sj.onc.1209053] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To ensure that their mRNAs are translated and that the viral proteins necessary for assembling the next generation of infectious progeny are produced, viruses must effectively seize control of the translational machinery within their host cells. In many cases, the ability to productively engage host translational components can determine if a given cell type can support viral replication, illustrating the critical importance of this task in the viral life cycle. Failure to interface properly with the host translational apparatus can compromise the productive growth cycle, resulting in an abortive infection and radically restricting viral replication. Not only have viruses become facile at commandeering this machinery, they are also particularly adept at manipulating cellular translation control pathways for their own ends. In this review, the mechanisms by which numerous viruses manipulate host translational control circuits are discussed. Furthermore, particular attention is devoted to understanding how interfering with the ability of a virus to properly regulate translation in its host can be exploited to generate oncolytic strains that selectively replicate in cancer cells.
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Affiliation(s)
- Ian Mohr
- Department of Microbiology, New York University School of Medicine, NY 10016, USA.
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42
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Parato KA, Senger D, Forsyth PAJ, Bell JC. Recent progress in the battle between oncolytic viruses and tumours. Nat Rev Cancer 2005; 5:965-76. [PMID: 16294217 DOI: 10.1038/nrc1750] [Citation(s) in RCA: 406] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
In the past 5 years, the field of oncolytic virus research has matured significantly and is moving past the stage of being a laboratory novelty into a new era of preclinical and clinical trials. What have recent anticancer trials of oncolytic viruses taught us about this exciting new line of therapeutics?
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Affiliation(s)
- Kelley A Parato
- Centre for Cancer Therapeutics, Ottawa Health Research Institute, 503 Smyth Road, Ottawa, Ontario, Canada K1H 8L6
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43
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Hermiston TW, Kirn DH. Genetically based therapeutics for cancer: similarities and contrasts with traditional drug discovery and development. Mol Ther 2005; 11:496-507. [PMID: 15771953 DOI: 10.1016/j.ymthe.2004.12.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2004] [Accepted: 12/07/2004] [Indexed: 11/22/2022] Open
Abstract
The field of molecular therapeutics is in its infancy and represents a promising and novel avenue for targeted cancer treatments. Like the small-molecule and antibody therapeutics before them, however, the genetic-based therapies will face significant research and development challenges in their maturation toward an approved cancer therapy. To facilitate this process, we outline and examine in this review the drug development process, briefly summarizing the research and development paradigms that have accompanied the recent successes of the small-molecule and antibody-based cancer therapeutics. Using this background, we compare and contrast the research and development experiences of small-molecule and antibody therapeutics with genetic-based cancer therapeutics, using oncolytic viruses as a defined example of an experimental molecular therapeutic for cancer.
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Affiliation(s)
- Terry W Hermiston
- Department of Gene Therapy, Berlex Biosciences, Richmond, CA 94941, USA.
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44
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Campbell SA, Gromeier M. Oncolytic viruses for cancer therapy II. Cell-internal factors for conditional growth in neoplastic cells. Oncol Res Treat 2005; 28:209-15. [PMID: 15840970 DOI: 10.1159/000084010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recent advances in our understanding of virus-host interactions have fueled new studies in the field of oncolytic viruses. The first part of this review explained how cell-external factors, such as cellular receptors, influence tumor tropism and specificity of oncolytic virus candidates. In the second part of this review, we focus on cellinternal factors that mediate tumor-specific virus growth. An oncolytic virus must be able to replicate within cancerous cells and kill them without collateral damage to healthy surrounding cells. This desirable property is inherent to some proposed oncolytic viral agents or has been achieved by genetic manipulation in others.
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Affiliation(s)
- Stephanie A Campbell
- Deptartment of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
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45
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Nakamori M, Fu X, Pettaway CA, Zhang X. Potent antitumor activity after systemic delivery of a doubly fusogenic oncolytic herpes simplex virus against metastatic prostate cancer. Prostate 2004; 60:53-60. [PMID: 15129429 DOI: 10.1002/pros.20056] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Although conventional radiation therapy and surgery are potentially curative treatments for organ-confined prostate cancer, there are few effective treatments for metastatic disease. Oncolytic viruses have shown considerable promise for the treatment of solid tumors including prostate cancer. We recently demonstrated that incorporation of a cell membrane fusion capability into an oncolytic herpes simplex virus (HSV) can significantly increase the antitumor potency of the virus. METHODS We used a mouse model of primary and metastatic human prostate cancer established from PC-3M-Pro4 to evaluate three different types of oncolytic HSVs: non-fusogenic Baco-1, singly fusogenic Synco-2, and doubly fusogenic Synco-2D. RESULTS Our results show that Synco-2D has greater oncolytic activity than either Baco-1 or Synco-2 virus. Against lung metastases of human prostate cancer xenografts, intravenous administration of Synco-2D had produced a significant reduction of tumor nodules by day 40 post-inoculation as compared with Synco-2 (P < 0.05), Baco-1 (P < 0.01), and PBS control (P < 0.01). CONCLUSIONS We conclude that the doubly fusogenic Synco-2D is an effective therapeutic agent for human metastatic prostate cancer.
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Affiliation(s)
- Mikihito Nakamori
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, Texas 77030, USA
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46
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Mohr I. Neutralizing innate host defenses to control viral translation in HSV-1 infected cells. Int Rev Immunol 2004; 23:199-220. [PMID: 14690861 DOI: 10.1080/08830180490265600] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Lytic replication of many viruses activates an innate host response designed to prevent the completion of the viral lifecycle, thus impeding the spread of the infection. One branch of the host's complex reaction functions to incapacitate the cellular translational machinery on which the synthesis of viral polypeptides completely depends. This is achieved through the activation of specific protein kinases that phosphorylate eIF2 on its alpha subunit and inactivate this critical translation initiation factor. However, as continued synthesis of viral proteins is required to assemble the viral progeny necessary to transmit the infection to neighboring cells, viruses have developed a variety of strategies to counter this cellular response. Genetic and biochemical studies with herpes simplex virus type 1 (HSV-1) have revealed that the virus produces at least two discrete products at different times during its replicative program that act to prevent the accumulation of phosphorylated eIF2alpha. The gamma(1)34.5 gene product is expressed first, encoding a regulatory subunit that binds the cellular protein phosphatase 1alpha and regenerates pools of active eIF2 by removing the inhibitory phosphate from the alpha subunit. The second function, encoded by the product of the Us11 gene, specifies a double-stranded RNA-binding protein that prevents activation of PKR, a cellular eIF2alpha kinase. Together, both proteins cooperate to overcome the antiviral response of the host and properly regulate translation in HSV-1-infected cells.
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Affiliation(s)
- Ian Mohr
- New York University School of Medicine, Department of Microbiology, MSB 214, New York, New York 10016, USA.
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Hu JCC, Coffin RS. Oncolytic herpes simplex virus for tumor therapy. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2003; 55:165-84. [PMID: 12968536 DOI: 10.1016/s0074-7742(03)01007-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Affiliation(s)
- Jennifer C C Hu
- Cancer Cell Biology, Hammersmith Hospital Campus, Imperial College School of Medicine, London W12 0NN, United Kingdom
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Ward SL, Scheuner D, Poppers J, Kaufman RJ, Mohr I, Leib DA. In vivo replication of an ICP34.5 second-site suppressor mutant following corneal infection correlates with in vitro regulation of eIF2 alpha phosphorylation. J Virol 2003; 77:4626-34. [PMID: 12663769 PMCID: PMC152123 DOI: 10.1128/jvi.77.8.4626-4634.2003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2002] [Accepted: 01/14/2003] [Indexed: 11/20/2022] Open
Abstract
In animal models of herpes simplex virus type 1 (HSV-1) infection, ICP34.5-null viruses are avirulent and also fail to grow in a variety of cultured cells due to their inability to prevent RNA-dependent protein kinase (PKR)-mediated inhibition of protein synthesis. We show here that the inability of ICP34.5 mutants to grow in vitro is due specifically to the accumulation of phosphorylated eIF2 alpha. Mutations suppressing the in vitro phenotype of ICP34.5-null mutants have been described which map to the unique short region of the HSV-1 genome, resulting in dysregulated expression of the US11 gene. Despite the inability of the suppressor mutation to suppress the avirulent phenotype of the ICP34.5-null parental virus following intracranial inoculation, the suppressor mutation enhanced virus growth in the cornea, trigeminal ganglia, and periocular skin following corneal infection compared to that with the ICP34.5-null virus. The phosphorylation state of eIF2 alpha following in vitro infection with the suppressor virus was examined to determine if in vivo differences could be attributed to differential regulation of eIF2 alpha phosphorylation. The suppressor virus prevented accumulation of phosphorylated eIF2 alpha, while the wild-type virus substantially reduced eIF2 alpha phosphorylation levels. These data suggest that US11 functions as a PKR antagonist in vivo, although its activity may be modulated by tissue-specific differences in translation regulation.
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Affiliation(s)
- Stephen L Ward
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Mohr I. Genetic metamorphosis of herpes simplex virus-1 into a biological therapeutic for human cancer. Expert Opin Biol Ther 2003; 3:113-25. [PMID: 12718736 DOI: 10.1517/14712598.3.1.113] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Over the past decade, rapid progress has been made in engineering safe, replicating herpes simplex virus-1 (HSV-1) mutants for use as biological oncolytic agents in the treatment of human cancer. While initial efforts demonstrated the potential of HSV-1 mutants as antitumour agents, they relied on viruses that were not sufficiently attenuated. Following its identification as the major viral neurovirulence determinant, mutations in the gamma34.5 gene were subsequently incorporated into oncolytic strains. Despite the fact that gamma34.5 mutant derivatives can be safely administered to mice, non-human primates and humans, their efficacy is limited because, like many weakened viral strains, they replicate poorly in a number of cell types, including cancer cells. Strategies to improve the oncolytic properties of gamma34.5 mutant derivatives through further genetic manipulation are reviewed. In addition, traditional treatment modalities that incorporate viral inoculation, along with efforts to elicit an antitumour immune response following treatment with gamma34.5 derivatives, are discussed.
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Affiliation(s)
- Ian Mohr
- New York University School of Medicine, Department of Microbiology, 550 First Avenue, New York, NY 10016, USA.
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Liu BL, Robinson M, Han ZQ, Branston RH, English C, Reay P, McGrath Y, Thomas SK, Thornton M, Bullock P, Love CA, Coffin RS. ICP34.5 deleted herpes simplex virus with enhanced oncolytic, immune stimulating, and anti-tumour properties. Gene Ther 2003; 10:292-303. [PMID: 12595888 DOI: 10.1038/sj.gt.3301885] [Citation(s) in RCA: 552] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Herpes simplex virus type-1 (HSV1) in which the neurovirulence factor ICP34.5 is inactivated has been shown to direct tumour-specific cell lysis in several tumour models. Such viruses have also been shown to be safe in Phase I clinical trials by intra-tumoral injection in glioma and melanoma patients. Previous work has used serially passaged laboratory isolates of HSV1 which we hypothesized may be attenuated in their lytic capability in human tumour cells as compared to more recent clinical isolates. To produce ICP34.5 deleted HSV with enhanced oncolytic potential, we tested two clinical isolates. Both showed improved cell killing in all human tumour cell lines tested compared to a laboratory strain (strain 17+). ICP34.5 was then deleted from one of the clinical isolate strains (strain JS1). Enhanced tumour cell killing with ICP34.5 deleted HSV has also been reported by the deletion of ICP47 by the up-regulation of US11 which occurs following this mutation. Thus to further improve oncolytic properties, ICP47 was removed from JS1/ICP34.5-. As ICP47 also functions to block antigen processing in HSV infected cells, this mutation was also anticipated to improve the immune stimulating properties of the virus. Finally, to provide viruses with maximum oncolytic and immune stimulating properties, the gene for human or mouse GM-CSF was inserted into the JS1/34.5-/47- vector backbone. GM-CSF is a potent immune stimulator promoting the differentiation of progenitor cells into dendritic cells and has shown promise in clinical trials when delivered by a number of means. Combination of GM-CSF with oncolytic therapy may be particularly effective as the necrotic cell death accompanying virus replication should serve to effectively release tumour antigens to then induce a GM-CSF-enhanced immune response. This would, in effect, provide an in situ, patient-specific, anti-tumour vaccine. The viruses constructed were tested in vitro in human tumour cell lines and in vivo in mice demonstrating significant anti-tumour effects. These were greatly improved compared to viruses not containing each of the modifications described. In vivo, both injected and non-injected tumours showed significant shrinkage or clearance and mice were protected against re-challenge with tumour cells. The data presented indicate that JS1/ICP34.5-/ICP47-/GM-CSF acts as a powerful oncolytic agent which may be appropriate for the treatment of a number of solid tumour types in man.
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